OFFSET
1,1
FORMULA
A000010(a(n)) == 0 (mod 8).
MATHEMATICA
Select[Range[150], Divisible[EulerPhi[#], 8] &] (* Amiram Eldar, Oct 27 2022 *)
PROG
(Python)
from sympy.ntheory import totient
def isok(n): return totient(n) % 8 == 0
(PARI) isok(k) = Mod(eulerphi(k), 8) == 0; \\ Michel Marcus, Oct 27 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Darío Clavijo, Oct 26 2022
STATUS
approved